Pharmacological effects of o-chloro-alpha-[(tert.-butylamino)methyl]benzylalcohol hydrochloride (C-78) on the nervous systems and miscellaneous organs were studied. 1. Through a low dosage of C-78 had little influence on the central nervous system, a high dosage of C-78 had a little slow-waving effect on the spontaneous EEG in rabbits, inhibitory action of the convulsion caused by pentetrazol or electroshock in mice and anti-pyrogenic action in rabbits. C-78 also dose-dependently inhibited the increase of motility caused by amphetamine in mice. 2. Only high concentrations of C78 had a local anesthetic action on the cornea and the skin of the back in guinea pigs. 3. C-78 significantly increased non-esterified fatty acids (NEFA) and glucose contents of blood in rabbits, but these actions were inhibited by propranolol. Another, high dosage of C-78 had anti-ulcer and anti-inflammatory action. From the results of the previous experiments and this study, it was concluded that C-78 is a new beta 2-receptor stimulating drug where beta 2-receptor selectivity is greater than that of isoproterenol, salbutamol and clorprenaline.